Tape Measure with Retraction Spring Adjacent to Tape Reel

ABSTRACT

A tool, such as a tape measure, including a spring-based retraction system is shown. The retraction system includes a spiral spring that is located outside of and adjacent to a tape reel about which a tape blade is wound. This arrangement provides for a decreased housing height which improves the ability to grip and handle the tape measure.

CROSS-REFERENCE TO RELATED APPLICATION

The present application is a continuation of International ApplicationNo. PCT/US2019/043063, filed Jul. 23, 2019, which claims the benefit ofand priority to U.S. Provisional Application No. 62/702,724, filed Jul.24, 2018, both of which are incorporated herein by reference in theirentirety.

BACKGROUND OF THE INVENTION

The present invention relates generally to the field of tools. Thepresent invention relates specifically to a tape measure, measuringtape, retractable rule, etc., that includes a spring-based retractionsystem located outside of and/or adjacent to the tape reel.

Tape measures are measurement tools used for a variety of measurementapplications, including in the building and construction trades. Sometape measures include a graduated, marked blade wound on a reel and alsoinclude a retraction system for automatically retracting the blade ontothe reel. In some typical tape measure designs, the retraction system isdriven by a coil or spiral spring that is tensioned, storing energy asthe tape is extended, and that releases energy to spin the reel, windingthe blade back onto the reel. In typical tape measure designs, thespiral spring is located within the tape reel.

SUMMARY OF THE INVENTION

One embodiment of the disclosure relates to a tape measure with ahousing, an axle, a tape reel, an elongate tape blade, and a spiralspring. The axle is mounted within the housing and has a longitudinalaxis. The tape reel is rotatably mounted within the housing around theaxle and defines a radially outward-facing surface. The elongate tapeblade is wound around the radially outward-facing surface of the tapereel. The spiral spring is located within the housing and no spring islocated between the tape blade and the longitudinal axis in the radialdirection. When the elongate tape blade is unwound from the tape reel toextend from the housing the spiral spring stores energy, and the spiralspring releasing energy drives rewinding of the elongate tape blade onto the tape reel.

In one embodiment, a tape measure includes a housing, an axle, a tapereel, an elongate tape blade, and a spiral spring. The axle is mountedwithin the housing and defines a longitudinal axis. The tape reel isrotatably mounted within the housing around the axle and defines aradially outward-facing surface. The elongate tape blade is wound aroundthe radially outward-facing surface of the tape reel. The spiral springis located within the housing and no spring is located within thehousing that has an outer diameter less than a diameter of the radiallyoutward-facing surface of the tape reel.

In one embodiment, a tape measure includes a housing, an axle, a tapereel, an elongate tape blade, and a spiral spring. The axle is mountedwithin the housing and defines a longitudinal axis. The tape reel isrotatably mounted within the housing around the axle and defines aradially outward-facing surface and an inward-facing surface. Theelongate tape blade is wound around the radially outward-facing surfaceof the tape reel. The spiral spring is located within the housing and adiameter of the axle is at least one-third of a diameter of theinward-facing surface of the tape reel.

One embodiment of the disclosure relates to a tape measure with aspring-based retraction system including a reel, a spiral spring and anaxle. The reel and the spiral spring are rotatably coupled around theaxle. The reel includes a radially outward facing surface about which atape blade is wound. The spiral spring is located within the housingadjacent to the reel and/or adjacent to the tape blade such that thespiral spring is not surrounded in the radial direction by either theradially outward facing surface of the reel or the tape blade. Invarious embodiments, the outer diameter of the spiral spring is greaterthat the outer diameter of the radially outward facing surface. In someembodiments, the width of the spiral spring is less than the width ofthe tape blade.

Additional features and advantages will be set forth in the detaileddescription which follows, and, in part, will be readily apparent tothose skilled in the art from the description or recognized bypracticing the embodiments as described in the written description andclaims hereof, as well as the appended drawings. It is to be understoodthat both the foregoing general description and the following detaileddescription are exemplary.

The accompanying drawings are included to provide further understandingand are incorporated in and constitute a part of this specification. Thedrawings illustrate one or more embodiments and, together with thedescription, serve to explain principles and operation of the variousembodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a tape measure, according to anexemplary embodiment.

FIG. 2 is a perspective view of a housing for a tape measure with aretraction spring located outside of the tape reel, according to anexemplary embodiment.

FIG. 3 is a cross-sectional perspective view of a tape measure includinga retraction spring located outside of the tape reel, according to anexemplary embodiment.

FIG. 4 is a cross-sectional perspective view of a tape measure includinga retraction spring located outside of the tape reel, according toanother exemplary embodiment.

FIG. 5 is a cross-sectional perspective view of a tape measure includinga retraction spring located outside of the tape reel, according toanother exemplary embodiment.

FIG. 6 is a perspective view of the tape measure of FIG. 5 with aportion of the housing removed showing the retraction spring, accordingto an exemplary embodiment.

FIG. 7 is a first perspective view of a gear train of the retractionsystem of the tape measure of FIG. 5, according to an exemplaryembodiment.

FIG. 8 is a second perspective view of a gear train of the retractionsystem of the tape measure of FIG. 5, according to an exemplaryembodiment.

FIG. 9 is a cross-sectional perspective view of a tape measure includinga retraction spring located outside of the tape reel, according to anexemplary embodiment.

DETAILED DESCRIPTION

Referring generally to the figures, various embodiments of a tapemeasure are shown. Various embodiments of the tape measure discussedherein include an innovative retraction system designed to provide for acompact and/or easy to hold housing while at the same time providing fora long tape length within such a housing having a relatively small sizeor easy to hold dimensions.

As will generally be understood, in certain tape measure designs, aspring (typically a spiral spring) stores energy during tape bladeextension and applies a force/torque to a reel causing the tape blade towind on to the reel during tape blade retraction. In the typical tapemeasure designs, the spring is located within a central cavity of thetape reel, and in such tape measure designs, increasing spring energy toprovide for retraction of longer, wider and/or thicker measuring tapeblades typically requires use of a larger spiral spring. In designs inwhich the retraction spring is located within the tape reel, increasingspring size often requires an increase of the height dimension of thetape measure housing to accommodate the increase in spring size.However, Applicant has determined that increasing tape measuring housingheight leads to a housing shape that can be difficult for the user tohold.

Accordingly, as discussed herein, Applicant has developed variousinnovative tape measure blade retraction systems in which the retractionspring is located outside of and next to the tape reel. In thisarrangement, the height dimension of the tape measure housing can bedecreased because the spring does not need to fit within the tape reel,which in turn allows the diameter of the surface of the tape reel aboutwhich the tape blade is wound to be reduced to a small size based on theminimum coil diameter of the tape blade. Further, in the arrangementsdiscussed herein, the retraction spring is located adjacent to the tapereel such that the retraction spring and tape reel share a commoncentral rotational axis. In contrast to tape measure designs thatinclude an off-axis external (relative to the tape reel) retractionspring, the retraction systems discussed herein do not requirerelatively complicated or potentially inefficient transmissionmechanisms typically required in off-axis spring arrangements.

In addition, in various embodiments, the tape retraction systemdiscussed herein may utilize a gear train coupled to the spring, tapereel and housing in a manner that allows for further optimization oftape measure size and/or control of tape measure retraction. In somesuch embodiments, the spring and tape reel are both coupled to arotating arbor or axle. In some such embodiments, the gear train is areduction gear train that translates each rotation of the tape reel toless than one rotation of the axle, which in turn translates to asmaller number of spring windings per rotation of the tape reel. Inalternative embodiments, a gear train is not used. Further, in someembodiments, the tape measure includes a first spring located outside ofthe tape reel as discussed herein and a second spring located inside ofthe tape reel.

Referring to FIGS. 1-3, a length measurement device, tape measure,measuring tape, retractable rule, etc., such as tape measure 10, isshown according to an exemplary embodiment. In general, tape measure 10includes a housing 12 having a first part 14 and a second part 16. Tapemeasure 10 includes a tape blade 18 and, in the retracted position shownin FIGS. 1-3, tape blade 18 is wound or coiled onto a tape reel 20. Ingeneral, tape blade 18 is an elongated strip of material including aplurality of graduated measurement markings, and in specificembodiments, tape blade 18 is an elongated strip of metal material(e.g., steel material) that includes an outer most end coupled to a hookassembly 22. Tape blade 18 may include various coatings (e.g., polymercoating layers) to help protect tape blade 18 and/or the graduatedmarkings of the blade from wear, breakage, etc.

FIG. 2 shows a detailed perspective view of tape housing 12. In general,the various spring based retraction systems discussed herein provide atape housing with a relatively low height (for a given tape bladelength) with a relatively large width that Applicant believes allows forimproved handling/grip of the tape measure 10. As shown in FIG. 2,housing 12 has a maximum outer height dimension, H1, that is thedimension of the housing generally perpendicular to the tape bladeduring tape extension, and a maximum outer width dimension, W1, this isthe dimension that is parallel to the width of tape blade 18.

In various embodiments, H1 is greater than W1. In various embodiments,H1 is between 60 mm and 120 mm, and W1 is between 40 mm and 70 mm. In aspecific embodiment, the tape blade length is between 35 ft and 45 ft,H1 is between 75 mm and 100 mm, and W1 is between 54 mm and 60 mm. In aspecific embodiment, the tape blade length is between 20 ft and 30 ft,H1 is between 60 mm and 85 mm, and W1 is between 52 mm and 58 mm. Invarious embodiments, the ratio of H1/W1 is relatively low (for a giventape length) compared to a typical tape measure with a retraction springlocated within the tape reel. In various embodiments, H1/W1 is less than2 and more specifically is between 1.7 and 1.1.

Referring to FIG. 1, a tape lock 30 is provided to selectively engagetape blade 18, which acts to hold tape blade 18 and reel 20 in placesuch that an extended segment of tape blade 18 remains at a desiredlength. A slot 32 is defined along a forward portion of housing 12. Slot32 provides an opening in the tape measure housing 12, which allows tapelock 30 to extend into housing 12 and to engage with tape 18 or reel 20within housing 12. In addition, slot 32 provides a length sufficient toallow tape lock 30 to be moved relative to housing 12 between locked andunlocked positions. Below slot 32, an opening, such as tape port 34, isprovided in tape housing 12. In one embodiment, tape port 34 has anarcuate shape, corresponding to an arcuate cross-sectional profile oftape blade 18. Tape port 34 allows for the retraction and extension oftape blade 18 into and from housing 12 during tape extension andretraction.

Referring to FIG. 3, tape reel 20 is rotatably mounted within housing 12and positioned around an axle 24. In the embodiment shown, axle 24 isrotatably mounted within housing 12 such that axle 24 is allowed torotate relative to housing 12 during tape extension or retraction.However, in other embodiments, axle 24 may be fixed relative to housing.

As shown in FIG. 3, tape measure 10 includes a retraction system 40 thatincludes a spring, shown as spiral spring 26. In general, spiral spring26 is coupled to tape reel 20 in a manner such that spiral spring 26 iscoiled or wound to store energy during extension of tape 18 from housing12 and is unwound, releasing energy, driving rewinding of tape 18 ontotape reel 20 during retraction of tape 18 (e.g., following release orunlocking of the tape 18). Specifically, when tape blade 18 is unlockedor released, spring 26 expands, driving tape reel 20 to wind up tapeblade 18 and to pull tape blade 18 back into housing 12.

As shown in FIG. 3, the non-extended portion of tape 18 is wound onto aradially outward facing surface 38 a reel 20, which is surrounded byhousing 12. Reel 20 is rotatably disposed about an axis 28 of tapemeasure 10 defined by axle 24, and spring 26 is coupled to reel 20 andconfigured to drive reel 20 about rotation axis 28, which in turnprovides powered retraction of tape blade 18.

In general and in contrast to typical tape measure designs, spring 26 islocated adjacent to and outside of the portion of reel 20 that supportsthe coiled portion of tape blade 18. In this arrangement, spring 26 isalso located outside of and adjacent to the coiled portion of tape blade18. Thus, in this arrangement, no portion of tape blade 18 or of surface38 surrounds spring 26 in the radial direction. In other words, noportion of tape blade 18 or of surface 38 is located between spring 26and housing 12 in the radial direction relative to axle 24.

As can be seen in FIG. 3, because spring 26 does not need to fit withinsurface 38 or within the coiled portion of tape blade 18, thisarrangement allows the diameter of reel 20 measured at radially outwardfacing surface 38, shown as OD1, to be significantly smaller than indesigns in which the retraction spring is located within surface 38 orwithin the coiled portion of tape blade 18. Further, in suchembodiments, spring 26 has a maximum outer diameter, shown as OD2. Invarious embodiments, OD2 is greater than OD1, and specifically isgreater than two times OD1. Further, in various embodiments, spring 26has a width that is less than the width of tape blade 18, specifically awidth that is less than half the width of tape blade 18, and morespecifically, a width that is less than a third of the width of tapeblade 18.

In addition, as can be seen in FIG. 3, spring 26 and tape blade 18 sharea common rotational axis 28, defined by axle 24. Thus, spring 26 islocated adjacent to and spaced from tape blade 18 along axis 28 withinhousing 12. In contrast to some tape measure designs with springslocated outside of the tape reel, this arrangement allows spring 26 tobe coupled to tape reel 20 via a single common rotational axle 24,without requiring a complicated transmission mechanism utilized in sometape measures with external, off-axis, retraction springs.

In the specific arrangement of FIG. 3, reel 20 includes a central barrel50, a sidewall 52 and a spring spool, shown as spring wall 54. Centralbarrel 50 is a hollow cylindrical structure that defines radiallyoutward facing surface 38 about which tape blade 18 is wound. Sidewall52 is a flange structure that extends radially outward from centralbarrel 50. Spring wall 54 is a wall (e.g., a cylindrical wall) thatextends outward from and perpendicular to sidewall 52 and that surroundsaxis 28. In general, central barrel 50, a sidewall 52 and a spring wall54 are formed from a rigid structure that rotate together within housing12.

A radially outer end of spring 26 is coupled to spring wall 54, and aradially inner end of spring 26 is coupled to axle 24. The rigidconstruction of reel 20 couples spring 26 to tape blade 18 such thatextension of tape blade 18 causes winding of spring 26, and unwinding ofspring 26 drives rotation of reel 20 and retraction of tape blade 18.

In the specific embodiment shown in FIG. 3, axle 24 is rotatably coupledto housing 12, and retraction system 40 includes a gear train 42. Ingeneral, gear train 42 is coupled between axle 24 and tape reel 20allowing the number of rotations of axle 24 produced in response to eachrotation of reel 20 to be selected based on the designed gear ratio ofgear train 42. This in turn allows for control of the number of turnsexperienced by spring 26 in response to each turn of reel 20 whichallows for control of the torque profile and retraction characteristicsof spring 26.

As shown in FIG. 3, gear train 42 includes a plurality of planetarygears 56 located between tape reel 20 and housing post 58. As will beunderstood, in this arrangement, a ring gear 60 is formed along aportion of the inner diameter of tape reel 20, and a central or sun gear62 is formed along an outer diameter of housing post 58.

It should be understood that in other embodiments, retraction system 40need not include gear train 42. In some such embodiments, axle 24 may bedirectly coupled to reel 20, and the inner end of spring 26 may becoupled to an inner spring spool which is coupled to axle 24 viagearing.

Further, while FIG. 3 shows a single spring 26 located on the left sideof reel 20, in other embodiments, tape measure 10 can include twosprings 26, one located on either side of reel 20 along axis 28. In somedual-spring embodiments, the two springs 26 may function in series witheach other, and in another embodiment, the two springs 26 may functionin parallel with each other.

As will be understood, utilizing some epicyclic gear arrangements inwhich the input of the gear train is coupled to reel 20, the output iscoupled to axle 24 and spring 26 is coupled between reel 20 and axle 24,spring 26 is wound in the same direction as rotation of reel 20 duringtape extension, and in other embodiments, spring 26 is wound in theopposite direction of rotation of reel 20 during tape extension.

Referring to FIG. 4, another embodiment of tape measure 10 including aspiral spring based retraction system, such as retraction system 100, isshown and described. In general, retraction system 100 is substantiallythe same as retraction system 40 discussed above, except for thedifferences discussed herein. Similar to retraction system 40,retraction system 100 is configured to transmit rotational movement oftape reel 20 (e.g., during tape extension) to winding of spring 26, andupon release of tape blade 18, expansion of spring 26 drives rewindingof tape blade 18 onto tape reel 20.

As shown in FIG. 4, retraction system 100 includes a spring spool, shownas cylindrical wall 102. Cylindrical wall 102 is rigidly coupled tohousing 12, and in a specific embodiment, cylindrical wall 102 is formedfrom a single integral piece of material with a portion of housing 12. Aradially outer end of spring 26 is coupled to cylindrical wall 102, anda radially inner end of spring 26 is coupled to axle 24. In thisembodiment, axle 24 is rotatably coupled to housing 12, and the fixedconnection between spring 26 and wall 102 allows spring 26 to be woundaround axle 24 during tape extension.

Further, in the embodiment shown in FIG. 4, retraction system 100includes a gear train 104. In this arrangement, a ring gear wall, shownas cylindrical wall 106, is rigidly coupled to housing 12, and in aspecific embodiment, cylindrical wall 106 is formed from a singleintegral piece of material with a portion of housing 12. A ring gear 108is coupled to cylindrical wall 106. A central or sun gear 110 is coupledto tape reel 20. One or more planetary gears 112 are coupled to axle 24.

Similar to gear train 42, gear train 104 is coupled between axle 24 andtape reel 20 allowing the number of rotations of axle 24 produced inresponse to each rotation of reel 20 to be selected based on the gearratio of gear train 104. This in turn allows for control of the numberof turns experienced by spring 26 in response to each turn of reel 20allowing for control of the torque profile and retractioncharacteristics of spring 26.

Referring to FIGS. 5-8, another embodiment of tape measure 10 includinga spiral spring based retraction system, such as retraction system 120,is shown and described. In general, retraction system 120 issubstantially the same as retraction systems 40 and 100 discussed above,except for the differences discussed herein. Similar to retractionsystem 40, retraction system 120 is configured to transmit rotationalmovement of tape reel 20 (e.g., during tape extension) to winding ofspring 26, and upon release of tape blade 18, expansion of spring 26drives rewinding of tape blade 18 onto tape reel.

Retraction system 120 includes a spring spool, shown as cylindrical wall102, and a spring arbor or axle 122. A radially outer end of spring 26is coupled to cylindrical wall 102, and a radially inner end of spring26 is coupled to spring axle 122.

In the embodiment shown in FIGS. 5-8, retraction system 120 includes agear train 124. In this arrangement, a connecting structure, shown asdisk 126, is rigidly coupled to housing 12. In various embodiments, disk126 is a component separate from housing 12 that is rigidly coupled tohousing 12, and in other embodiments, disk 126 is integrally formed withhousing 12.

A ring gear 128 is coupled to disk 126. A central or sun gear 130 iscoupled to tape reel 20. One or more planetary gears 112 are coupled toaxle 24. A gear carrier 132 is coupled to spring axle 122. Gear carrier132 includes one or more posts 134 that support one or more planetarygears 136 located between sun gear 130 and ring gear 128. It should beunderstood that while FIGS. 5-8 show a single planetary gear 136, insome embodiments, each post of gear carrier 132 supports a planetarygear 136.

Similar to gear train 42, gear train 124 is coupled between spring axle122 and tape reel 20 allowing the number of rotations of spring axle 122produced in response to each rotation of reel 20 to be selected based onthe gear ratio of gear train 124. This in turn allows for control of thenumber of turns experienced by spring 26 in response to each turn ofreel 20 allowing for control of the torque profile and retractioncharacteristics of spring 26.

In various embodiments, the gear trains discussed herein may provide avariety of gear ratios to provide a desired level of winding of spring26 in response to each rotation of reel 20. In various embodiments, thegear ratio provided by gear trains 42, 104 and/or 124 is between 1.5 and6.5, specifically between 2.5 and 4.5 and more specifically between 3and 4. In specific embodiments, gear trains 42, 104 and/or 124 have agear ratio of 3.1, 3.4 or 3.75.

In various embodiments discussed herein, spring 26 is formed from SK4steel having a thickness of 0.38 mm and a width of 10 mm. In variousembodiments, spring 26 has an active length of 38-40 mm and a formedcoil diameter of 35-40 mm.

In various embodiments, the components of retraction system 120 maybecoupled or connected in various arrangements. In one embodiment, axle24, carrier 132 and spring axle 122 are rigidly coupled together suchthat all three components rotate together within the tape measurehousing. In one such embodiment, axle 24, carrier 132 and spring axle122 are formed from a single, integral piece of material. In anotherembodiment, axle 24 is rotatably coupled relative to the housing andrelative to carrier 132 and to spring axle 122. In another embodiment,axle 24 is rigidly fixed to the housing and carrier 132 and axle 122rotate about axle 24.

In various embodiments, tape measure 10 can include tape blades 18having various maximum extended lengths. In specific embodiments, themaximum extended length of tape blade 18 is less than 50 feet or morespecifically less than 40 feet. In various embodiments, the length oftape blade 18 is between 15 ft. and 40 ft., and in specific embodiments,the length of the tape blade 18 is 35 ft., 30 ft., 25 ft., or 16 ft.

In various embodiments, gear trains 42, 104 or 124 may be any one of avariety of epicyclic gear train designs. In specific embodiments, geartrains 42, 104 or 124 are any one of the gear arrangements shown anddescribed in ANSI/AGMA 6123-B06. In other embodiments, gear trains 42,104 or 124 include two or more epicyclic gear arrangements connected toeach in series in which the input of a first epicyclic gear arrangementis coupled to reel 20, the output of the first epicyclic geararrangement is coupled to the input of a second gear arrangement, andthe output of the second epicyclic gear arrangement is coupled to axle24. This pattern can be repeated for gear trains 42, 104 or 124 thatinclude, 3, 4, 5, etc. epicyclic gear trains in series. In otherembodiments, gear trains 42, 104 or 124 are a gear arrangement notdescribed in ANSPAGMA 6123-B06.

Examples

Table 1 below shows details of various tape measure designs according tothe various specific designs according to exemplary embodimentsdiscussed herein.

TABLE 1 Tape Spool Tape Tape Flat Tape Total Minor Housing HousingSpring Spring Length Width Thickness Diameter Tape OD Height WidthThickness Width Gear (ft) (mm) (mm) (mm) (mm) (mm) (mm) (mm) (mm) Ratio40.6 30.5 0.36 20 83.14 95.14 55.1 0.35 10 2.8 40.6 30.5 0.36 20 83.1495.14 55.1 0.38 10 3.4 40.6 30.5 0.36 20 83.14 95.14 55.1 0.45 10 4.340.6 30.5 0.36 20 83.14 95.14 55.1 0.5 10 5.3 40.6 30.5 0.36 20 83.1495.14 55.1 0.55 10 6.8 40.6 30.5 0.18 30 65.97 77.97 58.1 0.3 13 3.540.6 30.5 0.18 30 65.97 77.97 58.1 0.35 13 4.3 40.6 30.5 0.18 30 65.9777.97 58.1 0.45 13 7 25.6 30.5 0.36 20 67.06 79.06 54.1 0.3 9 2.4 25.630.5 0.36 20 67.06 79.06 54.1 0.4 9 3.8 25.6 30.5 0.36 20 67.06 79.0654.1 0.5 9 6.3 25.6 30.5 0.18 30 55.42 67.42 56.1 0.25 11 2.5 25.6 30.50.18 30 55.42 67.42 56.1 0.3 11 3.4 25.6 30.5 0.18 30 55.42 67.42 56.10.4 11 5.7

Referring to FIG. 9, another embodiment of tape measure 11 including aspiral spring based retraction system, such as retraction system 140, isshown and described. In general, retraction system 140 is substantiallythe same as retraction systems 40, 100 and 120 discussed above, exceptfor the differences discussed herein. Retraction system 140 includesfirst spring 142 and second spring 144, which are arranged on eitherside of tape reel 20 along longitudinal axis 28. Similar to retractionsystems 40, 100, and 120, retraction system 140 is configured totransmit rotational movement of tape reel 20 (e.g., during tapeextension) to winding of springs 142 and 144, and upon release of tapeblade 18, expansion of springs 142 and 144 drives rewinding of tapeblade 18 onto tape reel 20.

Further, in the embodiment shown in FIG. 9, retraction system 140includes a gear train 148. Gear train 148 includes a plurality ofplanetary gears 152 located between tape reel 20 and sun gear 156. Acentral or sun gear 156 is coupled to tape reel 20, and planetary gears154 are coupled to axle 146.

Similar to gear trains 42, 104 and 124, gear train 148 is coupledbetween axle 146 and tape reel 20 allowing the number of rotations ofaxle 146 produced in response to each rotation of reel 20 to be selectedbased on the gear ratio of gear train 148. This in turn allows forcontrol of the number of turns experienced by springs 142 and 144 inresponse to each turn of reel 20 allowing for control of the torqueprofile and retraction characteristics of springs 142 and 144.

Axle 146 includes a component, shown as cylinder 150, that extends alonga majority (e.g., at least 50%) of a length of axle 146 alonglongitudinal axis 28. In various embodiments axle 146 includes anannular wall defining a cylindrical surface having an interior that isat least partially hollow. Cylinder 150 defines a diameter OD3.Outward-facing surface 38 of tape reel 20 defines a diameter OD1 andinward-facing surface 36 of tape reel 20 defines a diameter OD4.

In various embodiments there is no spring between tape blade 18 and axle24 in a radial direction, and more generally between tape reel 20 andlongitudinal axis 28 in a radial direction. As a result, the ratio ofdiameter OD1 of outward-facing surface 38 to diameter OD3 of axles 24,122 and/or 146 may be less than in other tape measures in which a spiralspring is radially located between the tape reel and the axle. In oneembodiment, diameter OD3 of cylinder 150 is at least one-fourth as longas diameter OD1 of outward-facing surface 38, and more specificallydiameter OD3 of cylinder 150 is at least one-third as long as diameterOD1 of outward-facing surface 38, and more specifically diameter OD3 ofcylinder 150 is at least 35% as long as diameter OD1 of outward-facingsurface 38, and more specifically diameter OD3 of cylinder 150 is atleast 40% as long as diameter OD1 of outward-facing surface 38.

In various embodiments the ratio of diameter OD4 of inward-facingsurface 36 to diameter OD3 of axles 24, 122 and/or 146 may be less thanin other tape measures in which a spiral spring is radially locatedbetween the tape reel and the axle. In one embodiment, diameter OD3 ofcylinder 150 is at least one-fourth as long as diameter OD4 ofinward-facing surface 36, and more specifically diameter OD3 of cylinder150 is at least one-third as long as diameter OD4 of inward-facingsurface 36, and more specifically diameter OD3 of cylinder 150 is atleast 35% as long as diameter OD4 of inward-facing surface 36, and morespecifically diameter OD3 of cylinder 150 is at least 40% as long asdiameter OD4 of inward-facing surface 36.

In various embodiments, no spring located within housing 12 has an outerdiameter less than radially-outward facing surface 38 of tape reel 20.

It should be understood that the figures illustrate the exemplaryembodiments in detail, and it should be understood that the presentapplication is not limited to the details or methodology set forth inthe description or illustrated in the figures. It should also beunderstood that the terminology is for description purposes only andshould not be regarded as limiting.

Further modifications and alternative embodiments of various aspects ofthe invention will be apparent to those skilled in the art in view ofthis description. Accordingly, this description is to be construed asillustrative only. The construction and arrangements, shown in thevarious exemplary embodiments, are illustrative only. Although only afew embodiments have been described in detail in this disclosure, manymodifications are possible (e.g., variations in sizes, dimensions,structures, shapes and proportions of the various elements, values ofparameters, mounting arrangements, use of materials, colors,orientations, etc.) without materially departing from the novelteachings and advantages of the subject matter described herein. Someelements shown as integrally formed may be constructed of multiple partsor elements, the position of elements may be reversed or otherwisevaried, and the nature or number of discrete elements or positions maybe altered or varied. The order or sequence of any process, logicalalgorithm, or method steps may be varied or re-sequenced according toalternative embodiments. Other substitutions, modifications, changes andomissions may also be made in the design, operating conditions andarrangement of the various exemplary embodiments without departing fromthe scope of the present invention.

Unless otherwise expressly stated, it is in no way intended that anymethod set forth herein be construed as requiring that its steps beperformed in a specific order. Accordingly, where a method claim doesnot actually recite an order to be followed by its steps or it is nototherwise specifically stated in the claims or descriptions that thesteps are to be limited to a specific order, it is in no way intendedthat any particular order be inferred. In addition, as used herein, thearticle “a” is intended to include one or more component or element, andis not intended to be construed as meaning only one. As used herein,“rigidly coupled” refers to two components being coupled in a mannersuch that the components move together in a fixed positionalrelationship when acted upon by a force.

Various embodiments of the invention relate to any combination of any ofthe features, and any such combination of features may be claimed inthis or future applications. Any of the features, elements or componentsof any of the exemplary embodiments discussed above may be utilizedalone or in combination with any of the features, elements or componentsof any of the other embodiments discussed above.

What is claimed is:
 1. A tape measure comprising: a housing; an axlehaving a longitudinal axis, the axle is mounted within the housing; atape reel rotatably mounted within the housing around the axle, whereinthe tape reel defines a radially outward-facing surface; an elongatetape blade wound around the radially outward-facing surface of the tapereel; and a spiral spring located within the housing, wherein when theelongate tape blade is unwound from the tape reel to extend from thehousing the spiral spring stores energy, wherein the spiral springreleasing energy drives rewinding of the elongate tape blade on to thetape reel, and wherein no spring is located between the tape blade andthe longitudinal axis in the radial direction.
 2. The tape measure ofclaim 1, wherein no spring is located between the tape reel and thelongitudinal axis in the radial direction.
 3. The tape measure of claim1, wherein the spiral spring is a first spiral spring and the tapemeasure comprises a second spiral spring located within the housing, andwherein the first spiral spring and the second spiral spring are locatedon opposing sides of the tape reel along the longitudinal axis.
 4. Thetape measure of claim 1, wherein the spiral spring and the tape reelrotate around the longitudinal axis, and wherein the axle rotates withrespect to the housing.
 5. The tape measure of claim 1, wherein the tapereel comprises a central barrel that defines the radially outwardsurface around which the tape blade is wound, a sidewall that extendsradially outward-facing from the central barrel, and a spring wall thatextends outward from the sidewall around the longitudinal axis, andwherein an outer end of the spiral spring is coupled to the spring wall.6. The tape measure of claim 1, the tape measure further comprises agear train that is coupled between the axle and the tape reel, whereinduring extension of the elongate tape blade from the housing, each fullrotation of the tape reel results in less than a full rotation of theaxle.
 7. The tape measure of claim 6, wherein the gear train comprises aplurality of planetary gears and a central sun gear and has a gear ratiogreater than 1.5.
 8. A tape measure comprising: a housing; an axlehaving a longitudinal axis, the axle is mounted within the housing; atape reel rotatably mounted within the housing around the axle, the tapereel defining a radially outward-facing surface; an elongate tape bladewound around the radially outward-facing surface of the tape reel; and aspiral spring located within the housing, wherein when the elongate tapeblade is unwound from the tape reel to extend from the housing thespiral spring stores energy, wherein the spiral spring releasing energydrives rewinding of the elongate tape blade on to the tape reel, andwherein no spring located within the housing has an outer diameter thatis less than a diameter of the radially outward-facing surface of thetape reel.
 9. The tape measure of claim 8, wherein the spiral spring isa first spiral spring and the tape measure comprises a second spiralspring located within the housing, and wherein the first spiral springand the second spiral spring are located on opposing sides of the tapereel along the longitudinal axis.
 10. The tape measure of claim 8,wherein the tape reel comprises a central barrel that defines theradially outward-facing surface around which the tape blade is wound, asidewall that extends radially outward from the central barrel, and aspring wall that extends outward from the sidewall around thelongitudinal axis, and wherein an outer end of the spiral spring iscoupled to the spring wall.
 11. The tape measure of claim 8, the tapemeasure further comprises a gear train that is coupled between the axleand the tape reel, wherein the gear train comprises a plurality ofplanetary gears and a central sun gear.
 12. The tape measure of claim11, wherein the gear train provides a gear ratio during extension of theelongate tape blade from the housing such that tape reel rotations toaxle rotations has a ratio between 2.5 and 4.5.
 13. A tape measurecomprising: a housing; an axle having a longitudinal axis, the axle ismounted within the housing; a tape reel rotatably mounted within thehousing around the axle, the tape reel defining a radiallyoutward-facing surface and an inward-facing surface; an elongate tapeblade wound around the outward-facing surface of the tape reel; and aspiral spring located within the housing, wherein when the elongate tapeblade is unwound from the tape reel to extend from the housing thespiral spring stores energy, wherein the spiral spring releasing energydrives rewinding of the elongate tape blade on to the tape reel, andwherein a diameter of the axle is at least one-third of a diameter ofthe inward-facing surface of the tape reel.
 14. The tape measure ofclaim 13, wherein the axle comprises a cylindrical outer surface thatextends along a majority of a length of the axle, and wherein thediameter of the axle is a diameter of the cylindrical outer surface. 15.The tape measure of claim 14, wherein the axle rotates with respect tothe housing, the tape measure further comprises a gear train that iscoupled between the axle and the tape reel.
 16. The tape measure ofclaim 16, wherein the gear train comprises a plurality of planetarygears and a central sun gear.
 17. The tape measure of claim 16, whereinthe gear train provides a gear ratio during extension of the elongatetape blade from the housing such that tape reel rotations to axlerotations has a ratio between 2.5 and 4.5.
 18. The tape measure of claim18, wherein the gear ratio is between 3 and
 4. 19. The tape measure ofclaim 13 wherein the spiral spring is a first spiral spring and the tapemeasuring comprises a second spiral spring located within the housing,and wherein the first spiral spring and the second spiral spring arelocated on opposing sides of the tape reel along the longitudinal axis.20. The tape measure of claim 18, wherein there is no spring between theaxle and the tape blade in the radial direction.